Mental Health First Aid (MHFA) is a standardized, psychoeducational programme developed to empower the public to approach, support and refer individuals in distress by improving course participants' knowledge, attitudes and behaviours related to mental ill-health. The present paper aims to synthesize published evaluations of the MHFA programme in a meta-analysis to estimate its effects and potential as a public mental health awareness-increasing strategy. Fifteen relevant papers were identified through a systematic literature search. Standardized effect sizes were calculated for three different outcome measures: change in knowledge, attitudes, and helping behaviours. The results of the meta-analysis for these outcomes yielded a mean effect size of Glass's Δ = 0.56 (95% CI = 0.38 - 0.74; p < 0.001), 0.28 (95% CI = 0.22 - 0.35; p < 0.001) and 0.25 (95% CI = 0.12 - 0.38; p < 0.001), respectively. Results were homogenous, and moderator analyses suggested no systematic bias or differences in results related to study design (with or without control group) or 'publication quality' (journal impact factor). The results demonstrate that MHFA increases participants' knowledge regarding mental health, decreases their negative attitudes, and increases supportive behaviours toward individuals with mental health problems. The MHFA programme appears recommendable for public health action.

BackgroundSerious and debilitating symptoms of anxiety are the most common mental health problem worldwide, accounting for around 5% of all adult years lived with disability in the developed world. Avoidance behavior—avoiding social situations for fear of embarrassment, for instance—is a core feature of such anxiety. However, as for many other psychiatric symptoms the biological mechanisms underlying avoidance remain unclear.MethodsReinforcement learning models provide formal and testable characterizations of the mechanisms of decision making; here, we examine avoidance in these terms. A total of 101 healthy participants and individuals with mood and anxiety disorders completed an approach-avoidance go/no-go task under stress induced by threat of unpredictable shock.ResultsWe show an increased reliance in the mood and anxiety group on a parameter of our reinforcement learning model that characterizes a prepotent (pavlovian) bias to withhold responding in the face of negative outcomes. This was particularly the case when the mood and anxiety group was under stress.ConclusionsThis formal description of avoidance within the reinforcement learning framework provides a new means of linking clinical symptoms with biophysically plausible models of neural circuitry and, as such, takes us closer to a mechanistic understanding of mood and anxiety disorders.

Ketamine improves motivation-related symptoms in depression but simultaneously elicits similar symptoms in healthy individuals, suggesting that it might have different effects in health and disease. This study examined whether ketamine affects the brain’s fronto-striatal system, which is known to drive motivational behavior. The study also assessed whether inflammatory mechanisms—which are known to influence neural and behavioral motivational processes—might underlie some of these changes. These questions were explored in the context of a double-blind, placebo-controlled, crossover trial of ketamine in 33 individuals with treatment-resistant major depressive disorder (TRD) and 25 healthy volunteers (HVs). Resting-state functional magnetic resonance imaging (rsfMRI) was acquired 2 days post-ketamine (final sample: TRD n = 27, HV n = 19) and post-placebo (final sample: TRD n = 25, HV n = 18) infusions and was used to probe fronto-striatal circuitry with striatal seed-based functional connectivity. Ketamine increased fronto-striatal functional connectivity in TRD participants toward levels observed in HVs while shifting the connectivity profile in HVs toward a state similar to TRD participants under placebo. Preliminary findings suggest that these effects were largely observed in the absence of inflammatory (C-reactive protein) changes and were associated with both acute and sustained improvements in symptoms in the TRD group. Ketamine thus normalized fronto-striatal connectivity in TRD participants but disrupted it in HVs independently of inflammatory processes. These findings highlight the potential importance of reward circuitry in ketamine’s mechanism of action, which may be particularly relevant for understanding ketamine-induced shifts in motivational symptoms.